1. Technical Field
The present invention relates to a treatment liquid and a recording method using the same.
2. Related Art
An ink jet recording method is a method in which printing is performed by discharging small droplets of ink from fine nozzle heads to be flown and by adhering the small droplets of ink on a recording medium such as paper. The method has a feature that images with a high-resolution and a high-quality image can be printed at a high speed using a relatively inexpensive apparatus. In an ink composition used in such an ink jet recording method, various components such as a coloring material, a resin, water, and an organic solvent are used according to a recording medium used.
In a case where an image is recorded using the ink composition for ink jet recording containing such a coloring material (in particular, a pigment), a technique of coagulating the component such as a pigment on a recording medium using a solution including a coagulant or the like is known from the viewpoint of improving the quality of an image.
For example, JP-A-2010-115854 describes that after a reaction ink containing water and a reactant (coagulant) such as a polyvalent metal salt is attached to an ink non-absorbent or low-absorbent recording medium, a color ink containing a colorant is attached thereto, and by the action of the reactant, an image having a high color density can be recorded. In addition, JP-A-2010-23266 describes that an image having a high color density can be recorded on a recording medium having an absorbing layer such as coated paper by attaching a reaction liquid containing water and a polyvalent metal salt and an ink composition containing a colorant or the like.
In the treatment liquid (reaction liquid) as described in JP-A-2010-115854 and JP-A-2010-23266, water is contained as a major medium in order to favorably dissolve or disperse the coagulant (reactant) included therein. However, water included in the treatment liquid significantly reduces wettability with respect to a recording medium not having ink absorbency such as a film, and therefore, there is a problem that the treatment liquid itself is repelled on the recording medium. Accordingly, even in the case of using the treatment liquid, the image quality of an ink composition containing a coloring material (colorant) cannot be sufficiently improved in some cases.
For example, when an organic solvent is added to the treatment liquid in order to solve such a problem, the wettability with respect to an ink non-absorbent recording medium can be improved in some cases. However, the coagulant included in the treatment liquid has a high solubility in water, and has a low solubility in an organic solvent in many cases. For this reason, depending on the properties of the organic solvent added to the treatment liquid, the coagulant is less likely to be dissolved in the treatment liquid, and preservation stability of the treatment liquid is reduced. In addition, when an organic solvent is added to the treatment liquid, with reduction of the content of water in the treatment liquid, the coagulant is less likely to be dissolved in the treatment liquid, and preservation stability of the treatment liquid is reduced.